A recent study reveals that skiers, snowshoers, and snowmobilers venturing into backcountry regions are impacting wolverine populations more than previously realized.
Research conducted in the Columbia and Rocky Mountain ranges, including Banff National Park, indicates that areas with increased recreational activities and roadways support fewer wolverines.
While it was already known that wolverines tend to avoid human presence, this study suggests that the effects extend beyond merely steering clear of hikers.
“Recreation is not as harmless as we once believed,” stated Mirjam Barrueto, the author of the study.
Barrueto, along with her research team from the University of Calgary and in collaboration with Parks Canada, investigated wolverines across an area of 80,000 square kilometers. This specific region was selected due to its suitability as wolverine habitat.
Based on prior studies, scientists anticipated the habitat could sustain approximately 500 to 600 wolverines.
However, the findings revealed that only around 300 wolverines currently inhabit the area.
A wolverine investigates a bait station set up by Mirjam Barrueto’s research team. Researchers placed beaver carcasses throughout the study area to attract wolverines and used the device pictured to collect fur samples for analysis. (Mirjam Barrueto)
The research highlighted that winter activities have a more significant effect compared to summer ones.
“Winter recreation typically leaves a much larger footprint because, during summer, access is largely limited to trails, and there are not many in our study area,” she pointed out. “In winter, snow covers everything, allowing skiers, snowmobilers, and heli-skiers to travel almost anywhere.”
Barrueto expressed surprise at the extent to which people penetrate what she considered remote wilderness.
Females wolverines are especially susceptible to disturbances while nurturing their young, as they give birth in winter and create dens in specific locations. Disruptions can cause them to abandon food caches or expend energy evading people instead of caring for their kits.
Barrueto suggests one possible solution is to identify these critical areas and temporarily restrict public access during sensitive winter months.
Additionally, the study found that as road numbers increased, the population of female wolverines declined, although this was not observed in males.
Jason Fisher, a wildlife ecologist and professor at the University of Victoria who was not part of the research, remarked that the study area comprises largely untouched land, which underscores the significance of the findings.
“We depend on the Rocky Mountains, especially national parks, as crucial habitats for wolverine populations,” he said. “It is concerning that they are struggling in an area designated for protection.”
Researchers Aerin Jacob (left) and Mirjam Barrueto (right) baiting a camera station in the Columbia Mountains, April 2018. (Michele Hueber)
Previous studies indicate that wolverines may begin avoiding an area after just three or four groups have traversed it over a few weeks.
This suggests that it is not merely the volume of people that is critical, according to Barrueto. Even minimal human activity can lead to a decline in the local wolverine population.
“Whether it is 100 people daily or 1,000, this particular species vanishes regardless,” Barrueto stated.
She advocates for keeping people on existing trails rather than creating new ones or venturing off-trail, which would provide wolverines the necessary space.
A camera captures a female wolverine at one of the sampling stations. (Mirjam Barrueto)
Fisher emphasized that conserving habitat is only part of the overall solution.
Wolverines also face threats from trapping, hunting, and vehicle collisions, and he argued that these mortality factors must be better managed as the population has little tolerance for additional losses.
“We can make a difference,” Fisher stated. “But it is crucial that we make these decisions now and take wolverine conservation seriously.”
He noted that wolverines have thrived in these mountains for millennia.
“An incredible species that has persisted since the last ice age,” Fisher remarked. “I want to see them continue to endure for much longer.”